GLOBAL POSITIONING SYSTEM

A Technical Seminar Report submitted inpartial

fulfillment for the award of the degree of
BACHELOR OF TECHNOLOGY

IN

COMPUTER SCIENCE AND ENGINEERING

Submitted by

T.TARUN 21X01A0559

Under the esteemed guidance of

Mr. G. Sunil Kumar M.Tech, (Ph.D)
Assistant Professor
School of Computer Science and engineering

www.nrcmec.org

November 2024
 School of Computer Science

CERTIFICATE
This is to certify that the Technical Seminar report entitled “GLOBAL
POSITIONING SYSTEM” is the bonafide work done by T. TARUN, 21 X01 A0559 ,
in partial fulfillment of the requirements for the award of the degree of Bachelor of
Technology in Computer Science and Engineering, from Jawaharlal Nehru Technological
University Hyderabad, during the year 2021-2025.

Project Guide Head of the Department

Mr. G. Sunil Kumar Dr. G. Ramu
Assistant Professor Professor & Head
School of Computer Science, School of Computer Science,
Narsimha Reddy Engineering College Narsimha Reddy Engineering College
Maisammaguda, Kompally, Secunderabad Maisammaguda, Kompally, Secunderabad
 ABSTRACT

The Global Positioning System (GPS) is a satellite-based navigation system that

provides accurate location and time information globally. Initially developed by the U.S.
Department of Defense for military purposes, GPS has become an essential tool for civilian
applications. It consists of a network of at least 24 satellites that continuously transmit signals
to ground-based receivers. By employing trilateration, these receivers calculate their precise
position by measuring the time it takes for signals from multiple satellites to reach them,
allowing for three-dimensional positioning with high accuracy. GPS has transformed various
sectors, including transportation, agriculture, emergency services, and logistics, enabling route
optimization, precision farming, and efficient incident response. The integration of GPS with
mobile devices has further broadened its applications, facilitating location-based services such
as ride-sharing and geolocation marketing. However, challenges like signal degradation in
urban areas and atmospheric interference persist. Advances in technology, including multi-
constellation systems like GLONASS and Galileo, aim to enhance GPS accuracy and
reliability. As GPS continues to integrate with emerging technologies such as the Internet of
Things (IoT) and autonomous systems, its significance in modern society is set to expand,
impacting daily life and various industries. Future developments promise to address existing
challenges and broaden the system’s capabilities, solidifying GPS as an indispensable tool in
an increasingly interconnected world.By employing trilateration, these receivers calculate their
precise position by measuring the time it takes for signals from multiple satellites to reach
them, allowing for three-dimensional positioning with high accuracy. GPS has transformed
various sectors, including transportation, agriculture, emergency services, and logistics,
enabling route optimization, precision farming, and efficient incident response. The integration
of GPS with mobile devices has further broadened its applications, facilitating location-based
services. .
 LISTOFFIGURES

FIGURE NUMBER FIGURE NAME PAGE NUMBER

Fig 1 gps working 2

Fig 2 control segement 3

Fig 3 receiver works 4

Fig 4 S-gps 7

Fig 5 google maps 10

Fig 6 Amazon 11

Fig 7 Future of gps 12

Fig 8 Historyof gps 13

 CONTENTS

CHAPTER NAME PAGE NUMBER

1.INTRODUCTION 1

2.HOW GPS WORKS 2

2.1 SPACE SEGEMENT

2.2 CONTROL SEGEMENT

2.3 USER SEGEMENT

3.HOW RECEIVER WORKS IN GPS 4

4.TYPES OF GPS 5

4.1 A-GPS

4.2 S-GPS

4.3D-GPS

5.EXAMPLES OF GPS 10

6.THE FUTURE OF GPS 12

7.THE HISTORY OF GPS 13

8.CONCLUSION 14

9.REFERENCES 15
GPS
1.INTRODUCTION

The Global Positioning System (GPS) is a revolutionary technology that has

transformed navigation and location-based services since its inception.
Developed by the U.S. Department of Defense in the 1970s, GPS was initially designed
for military applications but has since evolved into a critical tool for civilian use across
various sectors. At its core, GPS relies on a constellation of satellites orbiting the Earth,
which transmit signals to ground-based receivers. These receivers utilize the principle of
trilateration to accurately determine their location in three-dimensional space by
calculating the time it takes for signals from multiple satellites to arrive.

The impact of GPS is profound, influencing fields such as transportation, agriculture,

emergency response, and telecommunications. transportation, GPS has enabled real-
time navigation, route optimization, and efficient fleet management, significantly
enhancing mobility. In agriculture, it facilitates precision farming, helping farmers
maximize crop yields and minimize resource waste. Emergency services rely on GPS
for rapid response and accurate location tracking during crises. Additionally, the
integration of GPS with mobile devices has led to the rise of location-based
applications, changing how we interact with our environment.

Despite its widespread adoption, GPS faces challenges such as signal degradation in urban
areas and vulnerability to interference. However, ongoing advancements in satellite
technology and the emergence of multi- constellation systems promise to enhance its
reliability and accuracy. As we move into an increasingly interconnected world, the
relevance.
The future of GPS is poised for remarkable advancements that will enhance its accuracy,
reliability, and applications across various fields. With the integration of multiple global
navigation satellite systems (GNSS) like Galileo, GLONASS, and users can expect
improved positioning l continue to grow.

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GPS

2.HOW GPS WORKS

GPS works by communication between its different components, similar to

GLONASS, BeiDou, and Galileo satellites. The global positioning system (GPS) has
three parts or elements. These components work together to make sure that the navigation,
timing, and positioning information sent across are consistently accurate. The parts are the
space segment, control segment, and receivers.

Fig.1.1 gps working

Fig 1 GPS Works

1. Space segment

This GPS component is made from a constellation of 31 satellites that revolve in a

specific orbit around the earth. They are located at the height of 20,000 kilometers
above the planet, and each of them continuously sends out microwave signals sensed
by the preset receivers. The space segment of the Global Positioning System.

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GPS

2. Control segment

control segment is also known as the ground segment. This global positioning system
component is very similar to a tower station. The control segment is responsible for
managing and ensuring the proper functionality of the satellites.

The control segment comprises a master control station, a backup master control
station, several command antennas, control antennas, and monitoring sites.

Fig 2 Control Segement

3. Receivers or user segment

Receivers are the third and most common component of the GPS. They are found
embedded in virtually all smartphones and trackers in day-to-day devices. Their
application cuts across several industries, from transport and aviation to military,
automobile, and IoT. GPS receivers consist of an antenna and a processor.

The antenna is tuned to pick up the frequency of wave signals being transmitted from
satellites. At the same time, the processor uses a method known as trilateration to decode
and interpret the information.

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GPS

3. HOW RECEIVERS WORK IN GPS

A GPS receiver can only work when it is in the line of sight of at least three satellites.
This is why GPS devices are less accurate when used indoors. Each satellite sends a
signal encrypted with the satellite’s location at the time of transmission and when it sent
the signal. A receiver uses the site from three satellites sending signals to the same
receiver and the time difference from the time of signal transmission to when it was
received.

PROCESS

A GPS receiver operates by capturing signals from multiple GPS satellites to

determine its precise location on Earth. The process begins with the receiver scanning the
sky for signals from at least four satellites, each transmitting a unique signal that contains
information about its position and the exact time the signal was sent. Using a method
called trilateration, the receiver measures the time it takes for each satellite's signal to
reach it, allowing it to calculate the distance to each satellite based on the speed of light.
Accurate timing is crucial; therefore, GPS satellites are equipped with atomic clocks, and
the receiver synchronizes its internal clock with these signals to ensure precise distance
calculations. Once the distances are determined, the receiver employs mathematical
calculations to pinpoint its three-dimensional location (latitude, longitude, and altitude).

Fig 3 Receiver
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GPS
4.TYPES OF GPS

The global positioning system has a widely varied application. It has also undergone
several modifications giving rise to the different types of GPS. While they all work using
the same fundamental principle, each class specializes in meeting specific demands. The
types of GPS systems include:

1.A-GPS

Assisted GPS (A-GPS) is a type of GPS that allows receivers to get information
from local network sources, which helps in the location of satellites. Assisted GPS is
usually used in areas where satellite signals cannot easily reach, probably due to trees or
tall buildings. However, there must be cellular networks for A-GPS to work.

Assisted GPS became necessary when GPS was introduced for commercial use. A-
GPS is extensively used in smartphones where it makes the phone’s location information
accessible by emergency call dispatch. The technology increases start-up time and allows
cell phones to lock into the navigation system even when the signal is weak, or their
phone is visible to only two satellites. Features: Speeds up the time to first fix (TTFF) by
providing additional location information, making it effective in urban environments
where satellite signals may be weak.

to get information from local network sources, which helps in the location of
satellites. Assisted GPS is usually used in areas where satellite signals cannot easily
reach, probably due to trees or tall buildings. However, there must be cellular networks
for A-GPS to work.

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GPS

2.S-GPS

Simultaneous GPS (S-GPS) is a modification of GPS that allows both voice data and
GPS signaling to be transmitted from a phone simultaneously. Both data types are sent
simultaneously rather than alternating the SPS signal and the reception for the telephone
call, and there is better sensitivity. This is particularly useful in emergencies to allow
service providers such as ambulances, fire stations, etc., to locate the source of a call
even as the call is ongoing.

The most common type, used in civilian applications like vehicle navigation,
smartphones, and outdoor recreation.

The term "S GPS" typically refers to the "Standard GPS," which is the fundamental
global positioning system utilized primarily for civilian applications. Standard GPS
operates using a constellation of satellites that transmit signals to GPS receivers on
Earth. These receivers calculate their precise location—latitude, longitude, and altitude
—by measuring the time it takes for signals from at least four satellites to reach them.
Standard GPS is widely used in everyday applications, including navigation for vehicles,
smartphones, and outdoor activities such as hiking and geocaching. While it provides
basic positioning and timing services, its accuracy can be affected by factors like signal
obstruction, atmospheric conditions, and multipath effects. Despite these limitations,
Standard GPSemains a vital tool in modern society, enabling efficient navigation and
location-based services across various industries. As technology evolves, enhancements
and integrations with other global navigation satellite systems (GNSS)

This is particularly useful in emergencies to allow service providers such as

ambulances, fire stations, etc., to locate the source of a call even as the call is ongoing.

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GPS

Fig.4 S-GPS

The importance of Standard GPS (S GPS) lies in its foundational role in navigation
and location-based services across numerous sectors. As the most commonly used form of
GPS, it provides essential positioning, navigation, and timing information, enabling users
to determine their precise location anywhere on Earth. This capability is crucial for
everyday applications, such as driving directions in vehicles, finding routes on
smartphones, and enhancing outdoor activities like hiking and geocaching. In various
industries, S GPS supports logistics and transportation by optimizing routes and
improving efficiency, which can lead to significant cost savings. Furthermore, it plays a
vital role in emergency services, allowing first responders to quickly locate incidents and
provide timely assistance. The integration of Standard GPS with other technologies.

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GPS
3.D-GPS

The usual range of accuracy for GPS is, at best, 15 Meters. D-GPS can narrow the
location error limit to 1 inch (2.5cm). It works using a network of fixed ground stations
that broadcast the calculated difference between the known fixed locations and the
satellite location. D-GPS is applied by the United States and the Canadian Coast Guards.
(DGPSs) supplement and enhance the positional data available from (GNSSs). A DGPS
can increase accuracy of positional data by about a thousandfold, from approximately 15
metres (49 ft) centimetres.

GPS (D-GPS) is a correction technique used to increase the accuracy of location data
obtained from a traditional GPS receiver. D-GPS is an enhancement to GPS, providing a
better sense of the actual location of an object or person.

The usual range of accuracy for GPS is, at best, 15 Meters. D-GPS can narrow the
location error limit to 1 inch (2.5cm). It works using a network of fixed ground stations
that broadcast the calculated difference between the known fixed locations and the
satellite location. D-GPS is applied by the United States and the Canadian Coast Guards.

Differential GPS (DGPS) is an enhanced version of the standard Global Positioning

System (GPS) designed to improve the accuracy of position measurements. While
standard GPS typically provides location accuracy within about 5 to 10
meters.The (USCG) previouran DGPS in the United States radio
between 285 kHz and 325 kHz near major waterways and harbors. It was discontinued in
March 2022. The USCG's DGPS was known as NDGPS (Nationwide DGPS) and was
jointly administered by the Coast Gua It consisted of broadcast sites located throughout
the inland and coastal portions of the United States including Alaska, Hawaii and Puerto
Rico. (CCG) also ran a separate DGPS system, but discontinued its use on December 15,
2022. Other countries have their own.

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GPS

4.Non-differential GPS

Non-differential GPS, as opposed to differential GPS, uses direct satellite signals

to deduce positioning. It is less accurate than D-GPS, but has a significantly more
comprehensive range of use.

Non-Differential GPS refers to the standard Global Positioning System (GPS) that
operates without the use of additional correction signals provided by ground-based
reference stations. In this mode, a GPS receiver relies solely on signals from a
constellation of satellites to determine its position, typically achieving accuracy within
about 5 to 10 meters under ideal conditions.

Factors such as atmospheric conditions, signal blockage from buildings or trees,

and multipath effects (where signals reflect off surfaces before reaching the receiver) can
introduce errors in position calculations. Despite these limitations, non-differential GPS
remains widely used due to its accessibility, ease of use, and the availability of GPS
technology in various consumer devices. It serves as a foundational tool for location-
based services, providing users with essential navigation and timing information in many
day-to-day scenarios.

Non-Differential GPS refers to the standard Global Positioning System (GPS) that
operates without the use of additional correction signals provided by ground-based
reference stations. In this mode, a GPS receiver relies solely on signals from a
constellation of satellites to determine its position, typically achieving accuracy within
about 5 to 10 meters under ideal conditions.

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GPS

5.Examples of GPS

GPS solutions have been put across several use cases. Several companies have
developed software that takes advantage of GPS technology for commercial and
government purposes. Examples of the top GPS software are:

1. Google Maps Navigation

Google Maps is a commercial web mapping platform powered by the Google Cloud
Platform and marketed as an application to people worldwide. As of 2020, it was recorded
to be used by over one billion individuals every month. The original version of Google
Maps, released in 2005, was a combination of web-based mapping software, geospatial
data visualization, and real-time traffic analysis. Using a global positioning system,

Google Maps provides many features such as:

fig 5 Google maps

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GPS 2.Amazon Location Service

AWS recommends using Regional STS endpoints within your applications and
avoid using the global (legacy) STS endpoint. Regional STS endpoints reduce latency, build
in redundancy, and increase session token validity. For more information about configuring
your applications to use the regional STS endpoint, see AWS STS Regionalized endpoints
in the AWS SDKs and Tools Reference Guide. For more information about the global
(legacy) AWS STS endpoint, including how to monitor for use of this endpoint, see How to
use Regional AWS STS endpoints in the AWS Security blog.

Amazon Location Service is a fully managed service that enables developers to add
location capabilities to applications without the need for extensive infrastructure. It provides
features such as geolocation tracking, mapping, geofencing, and routing, leveraging data
from a variety of sources, including Amazon Web Services (AWS) and third-party
providers. This service allows businesses to track assets in real-time, create location-based
alerts, and visualize data on maps, making it valuable for applications in logistics,
transportation, and mobile app development. With built-in security and scalability, Amazon
Location Service helps organizations enhance user experiences and optimize operational
efficiency by integrating advanced location functionalities seamlessly into their
applications.

Fig 6 Amazon service

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GPS 6.FUTURE OF GPS

The future of GPS is poised for remarkable advancements that will enhance its
accuracy, reliability, and applications across various fields. With the integration of
multiple global navigation satellite systems (GNSS) like Galileo, GLONASS, and
BeiDou, users can expect improved positioning accuracy, particularly in urban
environments where signal obstruction is common. Technologies such as Real-Time
Kinematic (RTK) positioning and Precise Point Positioning (PPP) will enable centimeter-
level accuracy, making GPS invaluable for applications in surveying, agriculture, and
autonomous vehicles. As the risks of jamming and spoofing increase, future GPS systems
are likely to implement stronger encryption and authentication measures, particularly for
military and critical infrastructure uses. The growth of the Internet.

fig.7 Future of gps

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GPS
7.THE HISTORY OF GPS

The history of GPS dates back to the 1970s when the U.S. Department of Defense
initiated the development of a satellite-based navigation system to enhance military
operations. The project, initially called NAVSTAR, aimed to create a global positioning
system that could provide accurate location data anywhere in the world. The first satellite
was launched in 1978, and by the mid-1980s, a sufficient constellation of satellites was in
orbit to provide reliable positioning data. GPS technology became fully operational in
1995, offering civilian access to the system for the first time. Initially, civilian GPS
provided an accuracy of about 100 meters, but advancements over the years, including the
introduction of differential GPS (DGPS) in the 1990s, improved this accuracy
significantly. The system underwent modernization efforts, culminating in the deployment
of GPS III satellites, which began launching in 2018 and are designed to enhance security
and accuracy. Today, GPS is not only crucial for military applications but also plays an
integral role in everyday life, influencing sectors such as transportation, agriculture,
logistics, and emergency services, with billions of devices relying on its capabilities
worldwide

fig.7 history

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GPS
8.CONCLUSION

GPS is a fantastic tool of the 21st century offering many functions: waypoint,
MOB…. However, received information is not always reliable, and it would have been
interesting to see in which cases it is not. Furthermore, the space segment is completely
controlled by the American Army which enables them to completely remove the satellite
cover in certain countries in the event of a war… This aspect mobilized Europe towards
the creation of its own GPS system: the project GALILEO, which should be in place2008.
The future of GPS appears to be virtually unlimited; technological fantasies abound. The
system provides a novel, unique, and instantly available address for every square yard on
the surface of the planet– a new international standard for locations and distances. To the
computers of the world, at least, our locations may be defined not by a street address, a
city, and a state, but by a longitude and a latitude. With the GPS location of services
stored with phone numbers in computerized “yellow pages,” the search for a local
restaurant or the nearest gas station in any city, town, or suburb will be completed in an
instant. With GPS, the world has been given a technology of unbounded promise, born in
the laboratories of scientists who were motivated by their own curiosity to probe the
nature of the universe and our world, and built on the fruits of publicly supported basic
research.

the American Army which enables them to completely remove the satellite cover in
certain countries in the event of a war… This aspect mobilized Europe towards the
creation of its own GPS system: the project GALILEO, which should be in place2008.
The future of GPS appears to be virtually unlimited; technological fantasies abound. The
system provides a novel, unique, and instantly available address for every square yard on
the surface of the planet– a new international standard for locations and distances

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GPS
9.REFERENCES

www.course5i.com
www.mitsloan.mit.
www.geeksforgeeks
www.denverapa.org
www.researchgate.n

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